by Lindsay H. Jones, USA TODAY Sports

by Lindsay H. Jones, USA TODAY Sports

ENGLEWOOD, Colo. -- Just hours before surgery to replace an aortic valve in his heart, John Fox's mind was still on his football team.

But the voice on the other end of that phone call Sunday night reassured Fox that for now, football really doesn't matter â?? even if the Broncos are 7-1 and set to embark on the heart of their AFC West schedule.

"I just tried to comfort him and let him know to take care of himself and the family, and we'll keep this thing on track until he gets back," Broncos executive vice president of football operations John Elway said Monday.

Fox was out of surgery in North Carolina by the time his players began practicing Monday morning back in Colorado under the leadership of Jack Del Rio, who will serve as the interim head coach while Fox recovers. The Broncos have not set a definitive timetable for Fox's return, either to help Del Rio and the rest of the staff from afar, and or to the sidelines.

That decision will be up to Fox, his wife, Robin, and his doctors, and not dictated by football, Elway said.

"The doctors are going to tell us the right thing to do there. The concern is going to be with John's health -- not only for this season but John's health for the rest of his life," Elway said. "I think that we're in really good hands with Jack, and we just want to make sure we're making all the right decisions when it comes to John's return."

Del Rio was the obvious answer to replace Fox because of his nine years as a head coach in Jacksonville (2003-2011). Del Rio will continue in his role as defensive coordinator, which includes calling plays on game days.

Del Rio said he did not hesitate to accept Elway's offer to serve as interim head coach. He called it an honor.

Or as Fox would likely say, "Next man up."

Del Rio won't change much, if anything, with the way the Broncos are run. The practice and meeting schedule will remain the same, and the offense will still be orchestrated by coordinator Adam Gase and quarterback Peyton Manning. Del Rio will lean on his defensive assistants more during practices and during games when he needs to pay more attention to the offense or special teams, starting Sunday in San Diego.

The Broncos play three AFC West games, including a pair against undefeated Kansas City, in the next four weeks, and will also travel to New England before Fox is likely to return.

"We're on a mission to carry on and continue the things that coach Fox has instilled and started with this football team," Del Rio said. "This is coach Fox's team, I'm merely the person who is able to keep it running while he's leading."

It is a familiar scenario for tackle Winston Justice, who played for the Colts last year when Chuck Pagano was diagnosed with leukemia and had to take a leave of absence for 12 weeks. The Colts, led by interim head coach Bruce Arians, finished second in the AFC South and earned a wild-card playoff spot.

Elway called Indianapolis general manager Ryan Grigson on Sunday to talk about life with an interim head coach, and Del Rio said he planned to reach out to Arians.

But Justice said there was no magic trick that made the Colts successful under Arians, nor will there be for the Broncos to continue winning without Fox.

"When that happened, it brought the team closer, and I think the same thing can happen for this team," Justice told USA TODAY Sports. "[Arians] really didn't change anything. He inherited a team that had a new reason to play."

But Fox's presence will be missed around Dove Valley, if only for his loud laugh, raspy voice and enthusiasm.

"He's full of swag, it's just his leadership," safety Mike Adams said.